1. Field of the Invention
This invention relates to a punch for making a multiplicity of holes in paper.
2. Description of the Prior Art
A line of 30 holes are made in a sheet of paper having a standard size known as A4, and a line of 26 holes in a sheet of paper known as B5, when they are put in a file. FIG. 29 shows a known punch for making a multiplicity of holes in a sheet of paper having a standard size. It has a base plate 1 and a paper holder 2 attached to it rotatably, so that a sheet of paper 3 may be held in position between the base plate 1 and the paper holder 2. A ruler 4 forms an integral part of the paper holder 2 and has five notches 5 which are equally spaced apart from one another. A punch proper 6 has a protrusion 7 which is engageable with the notches 5 one after another, while it is slidable along the ruler 4 to make holes in the paper 3. The punch proper 6 has a cutting tool which can make six holes at a time. The punch proper 6 includes a spring, and is grasped and depressed by overcoming the force of the spring to cut holes.
The punch shown in FIG. 29 is of the smallest size available in the art, and is a very handy piece of office equipment which is convenient for use and storage. A considerably large grasping power is, however, required for operating the punch proper 6 by overcoming the force of the spring to cut six holes at a time. Therefore, the punch is useful for making holes through at most five sheets of paper at a time, and is difficult to employ for making holes through any greater number of sheets of paper at a time.
FIG. 28 shows another known type of punch designed for making 30 or 26 holes at a time. It includes a table 1 and a main body 2 between which paper is held, a lever 9 for selecting the number of holes to be made, which depends on the size of the paper, and a handle 8 which can be pushed down to make 30 or 26 holes in the paper. The force exerted by the handle 8 is so great that the punch shown in FIG. 28 can effectively make holes in a multiplicity of sheets of paper. The punch is, however, so large as to occupy a large space above a desk on which it is used in an office. Moreover, it is inconvenient for handling and storage.